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    Mattress Comparison
    Beautyrest Black C-Class mattress

    Beautyrest Black C-Class

    VS
    King Koil Xtended Life mattress

    King Koil Xtended Life

    Beautyrest Black C-Class vs. King Koil Xtended Life

    Side-by-side comparison of the Beautyrest Black C-Class (Hybrid) and King Koil Xtended Life (Hybrid). Compare comfort, cooling, support, value and more — based on our lab testing.

    Winner: Beautyrest

    By Sleep Sage Editorial Team

    Side-by-side mattress testing · 144+ comparisons published

    Updated May 2026
    Category
    Beautyrest Black C-Class
    King Koil Xtended Life
    Comfort
    9/10
    8.4/10
    Support
    9.2/10
    9.2/10
    Cooling
    9.4/10
    8.3/10
    Edge Support
    9.3/10
    9.1/10
    Motion Isolation
    8.9/10
    8.4/10
    Durability
    9.2/10
    9.3/10
    Value
    8.3/10
    8.2/10

    Quick Specs Comparison

    Spec
    Beautyrest Black C-Class
    King Koil Xtended Life
    Price (Queen)
    $2,999
    $2,549
    Type
    Hybrid
    Hybrid
    Firmness
    6/10
    7/10
    Height
    14.5 inches
    14 inches
    Trial
    100 nights
    120 nights
    Warranty
    10 years
    10 years
    Shipping
    Free white glove delivery
    Free shipping through most dealers

    Key Advantages

    Why Choose Beautyrest Black C-Class

    • Best cooling in the Black lineup
    • Versatile medium-firm feel suits most sleepers
    • BlackICE 4.0 + RightTemp foam combo

    Why Choose King Koil Xtended Life

    • Excellent support for heavier sleepers and couples over 400 lb combined
    • Best edge support in the King Koil lineup
    • High-density foams resist body impressions

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    Brands behind these picks

    Before you buy, read the brand: construction, pricing bands, trial and warranty terms, and how each company's lineup performed in our Encinitas lab.

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